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Glass Development for Treatment of LANL Evaporator Bottoms Waste

Description: Vitrification is an attractive treatment option for meeting the stabilization and final disposal requirements of many plutonium (Pu) bearing materials and wastes at the Los Alamos National Laboratory (LANL) TA-55 facility, Rocky Flats Environmental Technology Site (RFETS), Hanford, and other Department of Energy (DOE) sites. The Environmental Protection Agency (EPA) has declared that vitrification is the "best demonstrated available technology" for high- level radioactive wastes (HLW) (Federal Register 1990) and has produced a handbook of vitriilcation technologies for treatment of hazardous and radioactive waste (US EPA, 1992). This technology has been demonstrated to convert Pu-containing materials (Kormanos, 1997) into durable (Lutze, 1988) and accountable (Forsberg, 1995) waste. forms with reduced need for safeguarding (McCulhun, 1996). The composition of the Evaporator Bottoms Waste (EVB) at LANL, like that of many other I%-bearing materials, varies widely and is generally unpredictable. The goal of this study is to optimize the composition of glass for EVB waste at LANL, and present the basic techniques and tools for developing optimized glass compositions for other Pu-bearing materials in the complex. This report outlines an approach for glass formulation with fixed property restrictions, using glass property-composition databases. This approach is applicable to waste glass formulation for many variable waste streams and vitrification technologies.. Also reported are the preliminary property data for simulated evaporator bottom glasses, including glass viscosity and glass leach resistance using the Toxicity Characteristic Leaching Procedure (TCLP).
Date: November 20, 1998
Creator: Smith, DE; Piepel, GF; Veazey, GW; Vienna, JD; Elliott, ML; Nakaoka, RK et al.
Partner: UNT Libraries Government Documents Department

Corrosion Testing of Low-Activity Waste Glasses Fiscal Year 1998 Summary Report

Description: Analytical results are presented on the chemical composition and other physical properties of a glass, given the identification BNFL-A-S98, made at Pacific Northwest National Laboratory' that is representative of the low-activity waste glass composition proposed by BNFL, Inc.* for immobilization of envelope A double-shell tank wastes at the Hanford Site. This glass was prepared for use in a testing program to be conducted at Pacific Northwest National Laboratory and at Argonne National Laboratory for the purpose of characterizing its long-term corrosion behavior. Detailed examination of the glass microstructure using transmission electron microscopy showed structural features indicative of amorphous phase separation. A remelt was performed on a smaller batch (100 g) to ensure rapid cooling. The glass microstructure was reexamined and showed no evidence of phase separation. Selected long-term (some to 860 d) product consistency tests were terminated, and the leachates were analyzed on tests with three other representative low-activity waste glass formulations (L8- 1, L8-3, and L8-7). The results showed no evidence of corrosion rate acceleration at three times the duration of tests where another well-studied glass, LD6-5412, had been completely altered under identical test conditions. These tests (and others not discussed in this report) provide clear evidence that low-activity waste glasses with at least 20 mass% Na20 can be made that have excellent long-term corrosion resistance. However, glass composition has a large impact on long-term behavior and so careful experiments with several different techniques are essential to ensuring that a particular glass will have good long-term corrosion resistance.
Date: November 25, 1998
Creator: McGrail, BP; Lindenmeier, CW; Schaef, HT & Martin, PF
Partner: UNT Libraries Government Documents Department

Vitrification of Three Low-Activity Radioactive Waste Streams from Hanford

Description: As part of a demonstration for British Nuclear Fuels Limited, Incorporated (BNFL), the Immobilization Technology Section (ITS) of the Savannah River Technology Center (SRTC) has produced and characterized three low-activity waste (LAW) glasses from Hanford radioactive waste samples. The three LAW glasses were produced from radioactive supernate samples that had been treated by the Waste Processing Technology Section (WPTS) at SRTC to remove most of the radionuclides. These three glasses were produced by mixing the waste streams with between four and nine glass-forming chemicals in platinum/gold crucibles and heating the mixture to between 1120 and 1150 degrees C. Compositions of the resulting glass waste forms were close to the target compositions. Low concentrations of radionuclides in the LAW feed streams and, therefore, in the glass waste forms supported WPTS conclusions that pretreatment had been successful. No crystals were detected in the LAW glasses. In addition, all glass waste forms passed the leach tests that were performed. These included a 20 degrees C Product Consistency Test (PCT) and a modified version of the United States Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP).
Date: September 1, 1998
Creator: Ferrara, D.M.; Crawford, C.L.; Ha, B.C. & Bibler, N.E.
Partner: UNT Libraries Government Documents Department

Recycle Waste Collection Tank (RWCT) simulant testing in the PVTD feed preparation system

Description: (This is part of the radwaste vitrification program at Hanford.) RWCT was to routinely receive final canister decontamination sand blast frit and rinse water, Decontamination Waste Treatment Tank bottoms, and melter off-gas Submerged Bed Scrubber filter cake. In order to address the design needs of the RWCT system to meet performance levels, the PNL Vitrification Technology (PVTD) program used the Feed Preparation Test System (FPTS) to evaluate its equipment and performance for a simulant of RWCT slurry. (FPTS is an adaptation of the Defense Waste Processing Facility feed preparation system and represents the initially proposed Hanford Waste Vitrification Plant feed preparation system designed by Fluor-Daniel, Inc.) The following were determined: mixing performance, pump priming, pump performance, simulant flow characterization, evaporator and condenser performance, and ammonia dispersion. The RWCT test had two runs, one with and one without tank baffles.
Date: March 1, 1996
Creator: Abrigo, G.P.; Daume, J.T.; Halstead, S.D.; Myers, R.L.; Beckette, M.R.; Freeman, C.J. et al.
Partner: UNT Libraries Government Documents Department

Vitrification of Simulated Fernald K-65 Silo Waste at Low Temperature

Description: Vitrification is the technology that has been chosen to solidify approximately 18,000 tons of geologic mill tailings, designated as K-65 wastes, at the Fernald Environmental Management Project (FEMP) in Fernald, Ohio. The glass formula developed in this study for the FEMP wastes is a lithia substituted soda-lime-lithia-silica (SLLS) composition which melts at 1050 degrees Celsius. Low melting formulations minimize volatilization of hazardous species such as arsenic, selenium, chromium, and lead during vitrification. Formulation in the SLLS system avoids problematic phase separation known to occur in the MO-B2O3-SiO2 glass forming system (where MO = CaO, MgO, BaO, and PbO which are all constituents of the FEMP wastes). The SLLS glass passed the Environmental Protection Agency (EPA) Toxic Characteristic Leach Procedure (TCLP) for all the hazardous constituents of concern under the current regulations. The SLLS glass is as durable as the high melting soda-lime-silica glasses and is more durable than the borosilicate glasses previously developed for the K-65 wastes. Optimization of glass formulations in the SLLS glass forming system should provide glasses which will pass the newly promulgated Universal Treatment Standards which take effect of August 28, 1998.
Date: July 7, 1998
Creator: Jantzen, C.M. & Pickett, J.B.
Partner: UNT Libraries Government Documents Department

A Strategy to Conduct an Analysis of the Long-Term Performance of Low-Activity Waste Glass in a Shallow Subsurface Disposal System at Hanford

Description: Privatized services are being procured to vitrify low-activity tank wastes for eventual disposal in a shallow subsurface facility at the Hanford Site. Over 500,000 metric tons of low-activity waste glass will be generated, which is among the largest volumes of waste within the U.S. Department of Energy (DOE) complex and is one of the largest inventories of long-lived radionuclides planned for disposal in a low-level waste facility. Before immobilized waste can be disposed, DOE must approve a "performance assessment," which is a document that describes the impacts of the disposal facility on public health and environmental resources. Because the release rate of radionuclides from the glass waste form is a key factor determining these impacts, a sound scientific basis for determining their long-term release rates must be developed if this disposal action is to be accepted by regulatory agencies, stakeholders, and the public. In part, the scientific basis is determined from a sound testing strategy. The foundation of the proposed testing strategy is a well accepted mechanistic model that is being used to calculate the glass corrosion behavior over the geologic time scales required for performance assessment. This model requires that six parameters be determined, and the testing program is defined by an appropriate set of laboratory experiments to determine these parameters, and is combined with a set of field experiments to validate the model as a whole. Three general classes of laboratory tests are proposed in this strategy: 1) characterization, 2) accelerated, and 3) service condition. Characterization tests isolate and provide specific information about processes or parameters in theoretical models. Accelerated tests investigate corrosion behavior that will be important over the regulated service life of a disposal system within a laboratory time frame of a few years or less. Service condition tests verify that the techniques used in accelerated ...
Date: February 1998
Creator: McGrail, B. P.; Ebert, W. L.; Bacon, D. H. & Strachan, D. M.
Partner: UNT Libraries Government Documents Department

Immobilization of excess weapons plutonium in Russia

Description: In this paper, we examine the logic and framework for the development of a capability to immobilize excess Russian weapons plutonium by the year 2004. The initial activities underway in Russia, summarized here, include engineering feasibility studies of the immobilization of plutonium-containing materials at the Krasnoyarsk and Mayak industrial sites. In addition, research and development (R&D) studies are underway at Russian institutes to develop glass and ceramic forms suitable for the immobilization of plutonium-containing materials, residues, and wastes and for their geologic disposal.
Date: January 25, 1999
Creator: Borisov, G B; Jardine, L J & Mansourov, O A
Partner: UNT Libraries Government Documents Department

Status of immobilization of excess weapons plutonium in Russia

Description: In this paper, we examine the logic and framework for the development of a capability to immobilize excess Russian weapons plutonium by the year 2004. The initial activities underway in Russia, summarized here, include engineering feasibility studies of the immobilization of plutonium-containing materials at the Krasnoyarsk and Mayak industrial sites. In addition, research and development (R&D) studies are underway at Russian institutes to develop glass and ceramic forms suitable for the immobilization of plutonium-containing materials, residues, and wastes and for their geologic disposal.
Date: February 3, 1999
Creator: Borisov, G B; Jardine, L & Mansourov, O A
Partner: UNT Libraries Government Documents Department

Americium/Curium Melter 2A Pilot Tests

Description: Isotopes of americium (Am) and curium (Cm) were produced in the past at the Savannah River Site (SRS) for research, medical, and radiological applications. These highly radioactive and valuable isotopes have been stored in an SRS reprocessing facility for a number of years. Vitrification of this solution will allow the material to be more safely stored until it is transported to the DOE Oak Ridge Reservation for use in research and medical applications. To this end, the Am/Cm Melter 2A pilot system, a full-scale non- radioactive pilot plant of the system to be installed at the reprocessing facility, was designed, constructed and tested. The full- scale pilot system has a frit and aqueous feed delivery system, a dual zone bushing melter, and an off-gas treatment system. The main items which were tested included the dual zone bushing melter, the drain tube with dual heating and cooling zones, glass compositions, and the off-gas system which used for the first time a film cooler/lower melter plenum. Most of the process and equipment were proven to function properly, but several problems were found which will need further work. A system description and a discussion of test results will be given.
Date: May 1, 1998
Creator: Smith, M.E.; Fellinger, A.P.; Jones, T.M.; Miller, C.B.; Miller, D.H.; Snyder, T.K. et al.
Partner: UNT Libraries Government Documents Department

Process Control for Simultaneous Vitrification of Two Mixed Waste Streams in the Transportable Vitrification System

Description: Two highly variable mixed (radioactive and hazardous) waste sludges were simultaneously vitrified in an EnVitCo Transportable Vitrification System (TVS) deployed at the Oak Ridge Reservation. The TVS was the result of a cooperative effort between the Westinghouse Savannah River Company and EnVitCo to design and build a transportable melter capable of vitrifying a variety of mixed low level wastes.The two waste streams for the demonstration were the dried B and C Pond sludges at the K-25 site and waste water sludge produced in the Central Neutralization Facility from treatment of incinerator blowdown. Large variations occurred in the sodium, calcium, silicon, phosphorus, fluorine and iron content of the co- blended waste sludges: these elements have a significant effect on the process ability and performance of the final glass product. The waste sludges were highly reduced due to organics added during processing, coal-pile runoff (coal and sulfides), and other organics, including wood chips. A batch-by-batch process control model was developed to control glass viscosity, liquidus, and reduction/oxidation, assuming that the melter behaved as a Continuously Stirred Tank Reactor.
Date: May 1998
Creator: Cozzi, A. D.; Jantzen, C. M.; Brown, K. G. & Cicero-Herman, C.
Partner: UNT Libraries Government Documents Department

Melting, Solidification, Remelting, and Separation of Glass and Metal

Description: Several kinds of radioactive waste exist in mixed forms at DOE sites throughout the United States. These Wastes consist of radionuclides and some usefil bme materials. One purpose of waste treatment technologies is to vitrify the radionuclides into durable, stable glass-like materials to reduce the size of the waste form requiring final disposal. The other purpose is to recycle and reuse most of the usefi.d base materials. Thus, improved techniques for the separation of molten metal and glass are essential. Several high temperature vitrification technologies have been developed for the treatment of a wide range of mixed waste types in both the low-level waste and transuranic (TRU) mixed waste categories currently in storage at DOE sites throughout the nation. These processes include the plasma hearth process, which is being developed by Science Applications International Corporation (SAIC), and the arc melter vitrification process, which is being developed at Idaho National Engineering Laboratory. The products of these processes are an oxide slag phase and a reduced metal phase. The metal phase has the potential to be recycled within the DOE Complex. Enhanced slag/metal separation methods are needed to suppoti these process. A separation method is also needed for the radioactively contaminated scrap metal recycling processe; in order to obtain highly refined recycled metals.
Date: November 2, 1998
Creator: Ebadian, M. A.; C.Xin, R. & Dong, Z. F.
Partner: UNT Libraries Government Documents Department

Technical evaluation panel summary report: ceramic and glass immobilization options fissile materials disposition program

Description: This report documents the results of a technical evaluation of the merits of ceramic and glass immobilization forms for the disposition of surplus weapons-useable plutonium. The evaluation was conducted by a Technical Evaluation Panel (TEP), whose members were selected to cover a relevant range of scientific and technical expertise and represented each of the technical organizations involved in the Plutonium Immobilization Program. The TEP held a formal review at Lawrence Liver-more National Laboratory (LLNL) from July 2%August 1, 1997. Following this review, the TEP documented the review and its evaluation of the two immobilization technologies in this report to provide a technical basis for a recommendation by LLNL to the Department of Energy (DOE) for the preferred immobilization form. The comparison of the glass and ceramic forms and manufacturing processes was a tremendous challenge to the TEP. The two forms and their processes are similar in many ways. The TEP went to great effort to accurately assess what were, in many cases, fine details of the processes, unit operations, and the glass and ceramic forms themselves. The set of criteria used by the Fissile Materials Disposition Program (FMDP) in past screenings and down-selections was used to measure-the two options. One exception is that the TEP did not consider criteria that were largely nontechnical (namely international impact, public acceptance, and effects on other : DOE programs). The TEP� s measures and assessments are documented in detail. Care was taken to ensure that the data used were well documented and traceable to their source. Although no final conclusion regarding the preferred form was reached or explicitly stated in this report (this was not within the TEP� s charter), no �show stoppers� were identified for either form. Both forms appear capable of satisfying all the criteria, as interpreted by the TEP. The TEP ...
Date: December 23, 1997
Creator: Jostons, A; Armantrout, G; Brummond, W; Jantzen, CM; M; McKibben et al.
Partner: UNT Libraries Government Documents Department

Hanford Immobilized Low-Activity Waste Product Acceptance Test Plan

Description: 'The Hanford Site has been used to produce nuclear materials for the U.S. Department of Energy (DOE) and its predecessors. A large inventory of radioactive and mixed waste, largely generated during Pu production, exists in 177 underground single- and double-shell tanks. These wastes are to be retrieved and separated into low-activity waste (LAW) and high-level waste (HLW) fractions. The DOE is proceeding with an approach to privatize the treatment and immobilization of Handord''s LAW and HLW.'
Date: June 22, 1999
Creator: Peeler, D.
Partner: UNT Libraries Government Documents Department

Glass Formulation Development for INEEL Sodium-Bearing Waste

Description: Studies were performed to develop and test a glass formulation for immobilization of sodium-bearing waste (SBW). SBW is a high soda, acid high activity waste stored at the INEEL in 10 underground tanks. It was determined in previous studies that SBW?s sulfur content dictates the its loading in borosilicate glasses to be melted by currently assumed processes. If the sulfur content (which is ~4.5 mass% SO3 on a non-volatile oxide basis in SBW) of the melter feed is too high then a molten alkali sulfate containing salt phase accumulates on the melt surface. The avoidance of salt accumulation during the melter process and the maximization of sulfur incorporation into the glass melt were the main focus of this development work. A glass was developed for 20 mass% SBW (on a non-volatile oxide basis), which contained 0.91 mass% SO3, that met all the processing and product quality constraint determined for SBW vitrification at a planned INEEL treatment plant?SBW-22-20. This report summarizes the formulation efforts and presents the data developed on a series of glasses with simulated SBW. Summary
Date: August 1, 2002
Creator: Vienna, John D.; Buchmiller, William C.; Crum, Jarrod V.; Graham, Dennis D.; Kim, Dong-Sang; Macisaac, Brett D. et al.
Partner: UNT Libraries Government Documents Department

Development and Testing of ICV Glasses for Hanford LAW

Description: Preliminary glass compositions for immobilizing Hanford low-activity waste (LAW) by the in-container vitrification (ICV) process were fabricated at crucible- and engineering-scale and tested at Pacific Northwest National Laboratory. This testing showed that glasses with LAW loading of 20 mass% can readily be made and meet all product constraints by a far margin. It was found that the response constraint of the vapor hydration test (VHT) of less than 50 g/(m2•d) alteration rate was the most restrictive constraint placed on LAW glasses. Glasses with over 22 mass% Na2O can be made to meet this constraint along with all other product quality and processability constraints imposed by this process. The results of crucible melts with simulants were scaled-up to engineering scale and also tested with actual (radioactive) LAW. All the results suggest that the baseline glass can be successfully processed by the ICV technology and can meet all the constraints related to product quality.
Date: August 1, 2003
Creator: Kim, Dong-Sang; Vienna, John D.; Hrma, Pavel R.; Schweiger, Michael J.; Matyas, Josef; Crum, Jarrod V. et al.
Partner: UNT Libraries Government Documents Department

A Strategy to Assess Performance of Selected Low-Activity Waste Forms in an Integrated Disposal Facility

Description: An overall strategy for evaluating the long-term performance of three waste forms being considered for supplemental treatment of low-activity waste at Hanford is discussed. The same computational framework used to conduct the 2001 ILAW performance assessment will be used for all three waste forms. Cast stone will be modeled with a diffusion-advection transport model and bulk vitrified glass and steam reformed LAW will be modeled with a reactive chemical transport simulator. The recommended laboratory testing to support the supplemental LAW form selection includes single-pass flow-through (SPFT), product consistency (PCT), and vapor hydration tests for glass, SPFT and PCT tests for steam reformed LAW forms, and ANS 16.1 tests for cast stone. These and potentially other laboratory tests for the selected waste form(s) would also be the basis for more detailed studies needed to support a comprehensive long-term performance assessment should one or more of these waste forms be selected for disposal in an integrated disposal facility.
Date: August 22, 2003
Creator: McGrail, B PETER.; Bacon, Diana H.; Serne, R JEFFREY. & Pierce, Eric M.
Partner: UNT Libraries Government Documents Department

Feed Variability and Bulk Vitrification Glass Performance Assessment

Description: The supplemental treatment (ST) bulk vitrification process will obtain its feed, consisting of low-activity waste (LAW), from more than one source. One purpose of this letter report is to describe the compositional variability of the feed to ST. The other is to support the M-62-08 decision by providing a preliminary assessment of the effectiveness of bulk vitrification (BV), the process that has been selected to perform supplemental treatment, in handling the ST feed envelope. Roughly nine-tenths of the ST LAW feed will come from the Waste Treatment Plant (WTP) pretreatment. This processed waste is expected to combine (1) a portion of the same LAW feed sent to the WTP melters and (2) a dilute stream that is the product of the condensate from the submerged-bed scrubber (SBS) and the drainage from the electrostatic precipitator (WESP), both of which are part of the LAW off-gas system. The manner in which the off-gas-product stream is concentrated to reduce its volume, and the way in which the excess LAW and off-gas product streams are combined, are part of the interface between WTP and ST and have not been determined. This letter report considers only one possible arrangement, in which half of the total LAW is added to the off-gas product stream, giving an estimated ST feed stream from WTP. (Total LAW equals that portion of LAW sent to the WTP LAW vitrification plant (WTP LAW) plus the LAW not currently treatable in the LAW vitrification plant due to capacity limitations (excess)).
Date: January 10, 2005
Creator: Mahoney, Lenna A. & Vienna, John D.
Partner: UNT Libraries Government Documents Department

Corrosion of Metal Inclusions In Bulk Vitrification Waste Packages

Description: The primary purpose of the work reported here is to analyze the potential effect of the release of technetium (Tc) from metal inclusions in bulk vitrification waste packages once they are placed in the Integrated Disposal Facility (IDF). As part of the strategy for immobilizing waste from the underground tanks at Hanford, selected wastes will be immobilized using bulk vitrification. During analyses of the glass produced in engineering-scale tests, metal inclusions were found in the glass product. This report contains the results from experiments designed to quantify the corrosion rates of metal inclusions found in the glass product from AMEC Test ES-32B and simulations designed to compare the rate of Tc release from the metal inclusions to the release of Tc from glass produced with the bulk vitrification process. In the simulations, the Tc in the metal inclusions was assumed to be released congruently during metal corrosion as soluble TcO4-. The experimental results and modeling calculations show that the metal corrosion rate will, under all conceivable conditions at the IDF, be dominated by the presence of the passivating layer and corrosion products on the metal particles. As a result, the release of Tc from the metal particles at the surfaces of fractures in the glass releases at a rate similar to the Tc present as a soluble salt. The release of the remaining Tc in the metal is controlled by the dissolution of the glass matrix. To summarize, the release of 99Tc from the BV glass within precipitated Fe is directly proportional to the diameter of the Fe particles and to the amount of precipitated Fe. However, the main contribution to the Tc release from the iron particles is over the same time period as the release of the soluble Tc salt. For the base case used in this study ...
Date: July 31, 2006
Creator: Bacon, Diana H.; Pierce, Eric M.; Wellman, Dawn M.; Strachan, Denis M. & Josephson, Gary B.
Partner: UNT Libraries Government Documents Department

Cleanup Verification Package for the 300 VTS Waste Site

Description: This cleanup verification package documents completion of remedial action for the 300 Area Vitrification Test Site, also known as the 300 VTS site. The site was used by Pacific Northwest National Laboratory as a field demonstration site for in situ vitrification of soils containing simulated waste.
Date: March 13, 2006
Creator: Mitchell, S. W. Clark and T. H.
Partner: UNT Libraries Government Documents Department

Investigation of Tc Migration Mechanism During Bulk Vitrification Process Using Re Surrogate

Description: As a part of Bulk vitrification (BV) performance enhancement tasks, Laboratory scoping tests were performed in FY 2004-2005 to explore possible ways to reduce the amount of soluble Tc in the BV waste package. Theses scoping tests helped identify which mechanisms play an important role in the migration of Tc in the BV process (Hrma et al. 2005 and Kim et al. 2005). Based on the results from these scoping tests, additional tests were identified that will improve the understanding of Tc migration and to clearly identify the dominant mechanisms. The additional activities identified from previous studies were evaluated and prioritized for planning for Tasks 29 and 30 conducted in FY2006. Task 29 focused on the improved understanding of Tc migration mechanisms, and Task 30 focused on identifying the potential process changes that might reduce Tc/Re migration into the castable refractory block (CRB). This report summarizes the results from the laboratory- and crucible-scale tests in the lab for improved Tc migration mechanism understanding utilizing Re as a surrogate performed in Task 29.
Date: December 4, 2006
Creator: Kim, Dong-Sang; Bagaasen, Larry M.; Crum, Jarrod V.; Fluegel, Alex; Gallegos, Autumn B.; Martinez, Baudelio et al.
Partner: UNT Libraries Government Documents Department